Mathematics 0580 · IGCSE · Functions

Functions — practice question

The functions are defined by $f(x) = 2^{x-3}$, $g(x) = 2x - 1$, and $h(x) = \frac{5}{x - 4}$.

(a)[2]

Find the value of $f(6)$.

(b)[1]

Find the value of $g^{-1}(g(x + 21))$.

(c)[2]

Find the value of $x$ when $f(x) = h(84)$.

Worked solution & mark scheme

This 5-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Thus, $f(6)=8$.” …